Condensation product of formaldehyde, a phenol, and a ketone-amine condensate



Patented June 13, 1950 CONDENSATION PRODUCT OF FORMALDE- HYDE, A PHENOL, AND A KETONE-AMINE CONDENSATE Joseph R. Ingram, Nitro, W. Va., assignor to Monsanto Chemical Company, St. Louis, Mo a corporation of Delaware No Drawing. Application June 12, 1948, Serial N0. 676,349

. 16 Claims. (Cl. 260-45) l 2 The present invention relates to derivatives and acetone-aromatic amine condensation prodof the condensation products of aromatic amines uct assuming the latter to be a dihydroquinoline and ketones. More particularly, this invention or a dihydroacridine. Accordingly, the reactants relates to phenol-formaldehyde derivatives of the may be brought together in theoretical or equiproducts obtained by condensing aromatic amines 5 molecular proportions although it is generally with aliphatic ketones. preferable'to employ a molar proportion of form- In accordance with the present invention, it aldehyde somewhat in excess of the other reacthas been discovered that condensation products ants. Some control over the physical properties of aromatic amines and aliphatic ketones react of the final products may be exercised by control nearly quantitatively with a phenol and formaln of the proportion of formaldehyde. Thus. the dehyde to produce resinous products having valhardness of the product may be increased by inuable properties. creasing the proportion of formaldehyde. For in- The condensation products from which the new stance, treatment of one molecular proportion of derivatives are obtained may be prepared in the condensation product of aniline and acetone known manner by condensing an aromatic amine l: with one molecular proportion each of phenol and with an aliphatic ketone in the presence of a catformaldehyde gave a product which melted at alyst, as for example iodine, benzene sulfonic 85 0. whereas increasing the proportion of formacid, or sulfuric acid. While the acetone conaldehyde to 2.5 molecular proportions gave a densation products are the best known, condensaproduct melting around 100 C. tion products of other aliphatic ketones. as for The reactions take place in excellent yield even example methyl ethyl ketone and the aliphatic in the absence of condensation catalysts or posketones containing less than ten carbon atoms and sibly in the presence of the merest traces of acidic not more than two oxygen atoms described by condensing agents. Substantial amounts of acid Semon and Sloan in U. S. Patent 2,000,039, have condensing agent result in the formation of inbeen described and are suitable for use in the presfusible insoluble hard products. Consequently, ent invention. These condensation products are it is desirable to remove or neutralize any acid n lly ed to ompr e hiefly dih dr condensing -agents remaining in the aromatic quinoline bodies or dihydroacridine bodies but the amine-acetone condensation products. present invention is in nowise concerned with the The following specific embodiments illustrate correctness of these views. The condensation :n the invention in detail and are to be taken as ilproducts, whether derived from secondary or prilustrative and not limitative of the invention. mary amines, react nearly quantitatively with a The formaldehyde employed in the reactions was phenol and formaldehyde. Phenol itself, beta the usual commercial product consisting of an naphthol, and chloro phenol are typical examaqueous solution of 40% formaldehyde by volume ples of suitable phenols. Directions for condensor 37% by weight.

ing aromatic amines with acetone are furnished Example I in various publications, typical of which are U. S. Patent 2,062,885 to Ingram, U. S. Patent 2,000,039 The condensation product of p-amino diphenyl to Semon and Sloan, and U. S. Patent 1,807,355 and acetone,a commercial rubber antioxidant deto Ter Horst. Furthermore, the rearranged prod- 40 scribed by Ingram, U. S. 2,062,885, and considered uct obtained by heating the aniline-acetone conto consist principally of 6-phenyl 2,2,4-trimethyldensation product with a strong' non oxidizing 1,2-dihydroquinoline, was condensed with phenol mineral acid as described in U. S. Patent 2,004,752 and formaldehyde as described below. Substanto Ingramundergoes reaction with a phenol and tially 74.7 parts by weight (0.3 mol) of the pformaldehyde. amino diphenyl-acetone condensation product Preparation of the phenol-formaldehyde deand 28.2 parts by weight (0.3 mol) of phenol were rivatives of the condensation products may be heated together until a homogeneous liquid prodconducted in a single step or in separate stages not was produced. To the mixture so prepared by preliminary mixing of any two of the reactapproximately 44 parts by weight of 40% formants and finally condensing wi the th rd- OW- aldehyde was gradually added with cooling. After ever. the m t i fac y r s lts have been obthe addition of the formaldehyde, the charge was tained by first admixing the phenol with the heated gently and stirred for 4 /2 hours. While amine and gradually adding the formaldehyde to still warm and softthe contents of the reactor the mixture. were poured out, allowed to cool, then pulverized The reactions apparently involve the combinaand washed thoroughly with water. After drytion of one me] each of the phenol, formaldehyde ing. there was obtained 108 parts by weight of a 3 brown brittle resin readily soluble in benzene which had a melting point of 80-92 0.

Example II Into a suitable reactor there was charged 49.8 parts by weight (substantially 0.2 mol) of the condensation product of o-amino diphenyl and acetone described by Ingram, U. 8. 2,062,885 and considered to consist principally of 8-phenyl- 2,2,4-trimethyl-l2-dihydroquinoline and 18.8 parts by weight (substantially 0.2 mol) of phenol. The mixture was heated to 70 C. to obtain a homogeneous composition and to it there was added approximately 30 parts by weight of 40% formaldehyde. The formaldehyde was added slowly in small portions since the reaction was strongly exothermic. The temperature rose to 83 during the addition and was kept at 85-90 for six hours after the addition of the formaldehyde.

After working up the product as described in Example I, there was obtained 75.5 parts by weight of a resinous product.

Example 111 The condensation product of aniline and acetone, a commercial rubber antioxidant and considered to consist principally of 2,2,4-trimethyl 1,2-dihydro quinoline was reacted with phenol and formaldehyde in the following manner: Into a reactor of suitable capacity there was charged 190.3 parts by weight of the aniline-acetone condensation product (substantially 1.1 molecular proportions) and 103.4 parts by weight of phenol (substantially 1.1 molecular proportions) To the mixture, 147 parts by weight of 40% formaldehyde was added gradually. The temperature rose to 70 C. during the addition and was prevented from rising higher by suitable cooling. After the addition of the formaldehyde, the charge was heated at 8090 C. for three hours. About 1000 parts by weight ofv water was added to the viscous mass and the mixture stirred for a short time after which the solids were filtered oil and air dried. There was obtained 298 parts by weight of a resin-like product which melted at 95 C.

Example IV The condensation product of diphenylamine and acetone, a commercial rubber antioxidant described by Ter Horst in U. S. Patent 1,807,355, was stripped of the more volatile fraction by heat ing up to 147 C. vapor temperature under 3 mm. pressure (bath temperature 240 C.) and the residue reacted with phenol and formaldehyde as follows: 41.8 parts by weight (substantially 0.2 mol) of the residue believed to consist principally of dimethyl dihydroacridine (M. W. 209) was mixed with 18.8 parts by weight (substantially 0.2 mol) of phenol and about 55 parts by weight of ethyl alcohol and the mixture heated to 80 C. Substantially 15.0 parts by weight of 40% formaldehyde was added gradually and the charge stirred 5 hours at 80-85 C. The alcohol was removed by distillation under reduced pressure.

The residue was a dark resin. M. P. 95-09 C.

Example V and 23.5 parts by weight of phenol were charged into a suitable reactor and heated to 70 C. There was then added in small portions 37.5 parts by weight of 40% formaldehyde. The reaction mixture was heated at 80-85 C. for two hours after the addition of the formaldehyde. The brittle reaction mass was then pulverized, washed with water and dried. 68 parts by weight of a resinous product melting at 115-129 C. was obtained.

The products of this invention make valuable plasticizers and fillers for resins and rubber,

, sure to air or oxygen, as for example mineral oils.

vegetable oils, soap, gasoline, and rubber. While the condensation products of aromatic amines and acetone tend to discolor substances in which they are incorporated, the derivatives of this invention possess this disadvantage to a much lesser degree.

An especially important property of the products of this invention is their ability to prevent cross linking or continued polymerization of synthetic elastomers. While this phenomenon may be related to antioxidant activity, it is generally agreed that the effect is not confined to prevention of oxidation. For example, after the polymerization of butadiene and styrene in the manufacture of GR-S, it is necessary to add a substance to prevent continued hardening and embrittlement of the copolymer. Heat and oxygen greatly accelerate this hardening. The products of this invention are admirably suited for preventing continued hardening as illustrated by the soft smooth appearance of the copolymer obtained after heating in the presence of the new products.

GR-S latex type 1 containing no antioxidant was charged into a suitable container in amount equivalent to 100 parts by weight of the dry copolymer. 2.0 parts by weight of the antioxidant material was dissolved in benzene or other solvent and emulsified in water by the aid of a suitable dispersing agent, as for example dodecyl benzene sodium sulfonate. The emulsion was then added to the latex and blended thoroughly after which the copolymer was coagulated. The coagulum was washed free of salt and soap and then dried 30 minutes at C. Slabs of the products so prepared were placed on glass plates and exposed to circulating air for six days at C. after- Product Added to the Copolymer (million of Sample After Aging Hard, brittle, rough surface.

Smooth surface, soft and rub beii'zy, homogeneous throughon None p-Amiuo dighenyl-acetone condensed wit phenol and formaldeh de.

o-Am 0 di henyl-acetonc con- Do.

densed wit phenol and formaldehyde.

Aniline-acetone condensed with Do.

henol and formaldehyde.

D phenylamine-acetone condensed Do.

with barrel and formaldehyde.

Miner acid rearranged aniline- Do.

acetone condensed with phenol and formaldehyde.

The advantage of the new additives is also shown after compounding and curing stocks of the butadiene-styrene copolymer. Thus, after coa ulation of the GR-B latex to which an emulsion of one of the new antioxidants had been added and washing and drying the coagulum. vulcanizable stocks were compounded and cured in the usual manner and the vulcanizates artificially aged.

Stocks were compounded comprising,

Modulus oi Elasticity in lhsJin. at 300% elongation orig.- Per cant Antioxidant Aniline acetone condensed with phenol and iormaldehyde r 430 The lower modulus, higher tensile and elongation of the stock prepared from the copoLvmei' containing the antioxidant shows that the addi-- tive has inhibited cross linking and oxidation, thereby maintaining the rubbery properties to a greater degree.

As illustrative of the usefulness of the new products for inhibiting the deterioration of natural rubber, stocks were compounded compr sin Parts by Weight Smoked sheet rubber bon black Blanca-"n88 hiamla Aniline-acetone condensed with phenol and formaldehyde The stocks so compounded were vulcanized by heating for 60 minutes in a press in the usual manner at 135 C. and the cured products artificially aged by heating for six hours in a bomb at 121 C..and under an air pressure 80 pounds per square inch. The stress-strain properties of the aged rubber products together with the percentage of the original tensile Parts by Weight GR-S latex solids containing antioxidant 1 100. 0

GR-S latex solids without antioxidant- 100. 0, Carbon black 40. 0 40. 0 nliur- 2. 0 2. 0 N-Cyclohexyl z-benzothiazyl sulienamide 1.2 l.-2 Z c oxide 3. 0 8. 0 Hydrocarbon softener 8.0 8.0

The antioxidants 01! this invention may be employed in conjunction with other compositions than those specifically mentioned for the products of this invention are applicable generally to pure rubber 'or rubber compositions of the most varied nature. A rubber may be defined as a vulcanizable plastic material which possesses high extensibility under load coupled with the property of forcibly retracting to approximately its original size and shape after the load is removed. Examples of such products are India rubber, reclaimed rubber, balata. gutta percha. and other natural or synthetically prepared vulcanizable products which deteriorate upon aging or exposure to the atmosphere by absorption of ozwgen, whether or not admixed with fillers, pigments, or accelerating a ents.

As will be readily appreciated by those skilled in organic chemistry, numerous modifications of the procedures hereinbefore described can be made without departing from the spirit or scope of the present invention. Derivatives of the condensation products of acetone and other aromatic amines than those specifically mentioned may be prepared. The present invention is limited solely by the claims attached hereto as part of the present specification.

What is claimed is:

1. The resinous condensation product of at least one molecular proportion of formaldehyde and substantially one molecular proportion of phenol I and substantially one molecular proportion of the essentially acid free condensation product of acetone and a primary aromatic amine possessing only amino and hydrocarbon groups and consisting solely of the elements carbon, nitrogen. and hydrogen, the. molecular proportion of the acetone-amine condensation product being based on the assumption that it is a trimethyl dihydroquinoline.

2. The resinous condensation product of at least one molecular proportion of formaldehydeand substantially one molecular proportion of phenol and substantially one molecular proportion of the essentially acid free condensation product of acetone and aniline, the molecular proportion of the acetone-amine condensation product being based on the assumption that it is trimethyl dihydroquinoline.

3. The resinous condensation product of formaldehyde, phenol, and the essentially acid free condensation product of acetone and a primary aromatic amine possessing only amino and hydrocarbon groups and consisting solely of the elements carbon, nitrogen, and hydrogen, wherein the molecullar proportions of formaldehyde, phenol, and the acetone-amine condensation product are substantially equal, the molecular proportion of the acetone-amine condensation product being based on the assumption that it is a trimethyl dihydroquinoline.

4. The resinous condensation product of formaldehyde, phenol, and the essentially acid free condensation product of acetone and aniline, wherein the molecular proportions of formalderetainedare set forth below. hyde, phenol, and the acetone-amine condensa- Modulus of Elasticityin Tensile at Ult. 3 g Antioxidant llS-lilfii at 1:! lliilon .,t Tensile 011- 81' Retained Anilineacetone condensed with phenol and formaldehyde l, 610 2, 536 460 67 None 1, 310 1.915 480 54 I tion product are substantially equal, the molecu- "the acetone-amine condensation product being based on the assumption that it is a phenyl sub: stituted trimethyl dihydroquinoline.

6. The resinous condensation product of formaldehyde, phenol, and the essentially acid free condensation product of acetone and p -amino biphenyl, wherein the molecular proportions of formaldehyde, phenol, and the acetone-amine condensation product are substantially equal, the molecular proportion of the acetone-amine condensation product being based on the assumption that it is phenyl substituted trimethyl dihydroquinoline.

7. The method of preparing a resinous condensation product which comprises heating 1 to 2.5 molecular proportions of formaldehyde and substantially 1 molecular proportion of phenol and substantially 1 molecular proportion of the essentially acid free condensation product of acetone and a primary aromatic amine possessing only amino and hydrocarbon groups and consisting solely of the elements carbon, nitrogen, and hydrogen, the molecular proportion of the acetoneamine condensation product being based on the assumption that it is a trimethyLdihydroquinoline.

8. The method of preparing a resinous condensation product which comprises heating 1 to 2.5 molecular proportions of formaldehyde and substantially 1 molecular proportion of phenol and substantially 1 molecular proportion of the essentially acid-free condensation product of acetone and aniline, the molecular proportion of the acetone-amine condensation product being based on the assumption that it is trimethyl dihydroquinoline.

1 9. The method of preparing a resinous condensation product which comprises heating formaldehyde, phenol, and the essentially acid free condensation product of acetone and a primary aromatic amine possessing only amino and hydrocarbon groups consisting solely of the elements carbon, nitrogen, and hydrogen, wherein the molecular proportions of formaldehyde, phenol, and the acetone-amine condensation product are substantially equal, the molecular proportion of the acetone-amine condensation product being based on the assumption that it is a trimethyl dihydroquinoline.

10. The method of preparing a resinous condensation product which comprises heating formaldehyde, phenol, and the essentially acid free condensation product of acetone and aniline, wherein the molecular proportions of formaldehyde, phenol, and the acetone-amine condensation product are substantially equal, the molecular proportion of the acetone-amine condensation product being based on the assumption that it is trimethyl dihydroquinoline.

11. The method of preparing a resinous condensation product which comprises heating formaldehyde, phenol, and the essentially acid free 8 condensation product of acetone and an amino biphenyl possessing only amino and hydrocarbon groups and consisting solely of the elements carbon, nitrogen, and hydrogen, wherein the molecular proportions of formaldehyde, phenol, and the acetone-amine condensation product are substantially equal, the molecular proportion. of the acetone-amine condensation product being based on the assumption that it is a phenyl substituted trimethyl dihydroquinoline.

12. The method of preparing a resinous condensation product which comprises heating formaldehyde, phenol, and the essentially acid free condensation product of acetone and p-amino biphenyl, wherein the molecular proportions of formaldehyde, phenol, and the acetone-amine condensation product are substantially equal, the

molecular proportion of the acetone-amine condensation product being based on the assumption that it is phenyl substituted trimethyl dihydroquinoline.

13. The resinous condensation product of at least one molecular proportion of formaldehyde and substantially one molecular proportion of a mono hydroxy aromatic compound reactive therewith consisting of hydrogen atoms, an oxygen atom, at least 6 but not more than 10 carbon atoms and containing not more than one chlorine atom, said hydroxy substituent and chlorine atom being linked to the aryl nucleus, and substantially one molecular proportion of the essentially acid free condensation product of an aromatic amine possessing only amino and hydrocarbon groups and consisting solely of the elements carbon, nitrogen, and hydrogen, and containing at least one hydrogen atom linked to a nitrogen,.and an aliphatic ketone containing less than ten carbon atoms and not more than two oxygen atoms and consisting solely of the elements carbon, oxygen, and hydrogen, the molecular proportion of the ketone-amine condensation product being based upon the assumption that one molecular proportion of aromatic amine'yields one molecular proportion of allphatic ketone condensate.

14. The resinous condensation product of at least one molecular proportion of formaldehyde and substantially one molecular proportion of phenol and substantially one molecular proportion 01' the essentially acid free condensation product of acetone and a secondary aromatic amine possessing only amino and aromatic hydrocarbon groups and consisting solely of the elements carbon, nitrogen, and hydrogen, the molecular proportion of the acetone-amine condensation product being based on the assumption that it is a dihydroacridine.

15. The method of preparing a resinous condensation product which comprises heating 1 to 2.5 molecular proportions of formaldehyde and substantially 1 molecular proportion of a mono hydroxy aromatic compound reactive therewith consisting of hydrogen atoms, an oxygen atom,

,at least 6 but not more than 10 carbon atoms atlas consisting solely of the elements carbon, oxygen,

and hlifiiflgtii, the molecular proportion of tilt ketone-amine condensation product being based on the assumption that one molecular proportion of aromatic amine yields one molecular proportion of aliphatic ketone condensate.

16. The method of preparing a resinous condensation product which comprises heating 1 to 2.5 molecular proportions of formaldehyde and substantially 1 molecular proportion of phenol and substantially 1 molecular proportion of the essentially acid free condensation product of acetone and a secondary aromatic amine possessing only amino and aromatic hydrocarbon groups and consisting solely of the elements carbon,nitrogen, and hydrogen, the molecular proportion oi the acetone t 11. condensation and net B81118 tutti mi tilt compiler that it it drodine.

" NCES (CITED The following references are of record in the file of this patent: 

1.THE RESINOUS CONDENSATION PRODUCT OF AT LEAST ONE MOLECULAR PROPORTION OF FORMALDEHYDE AND SUBSTANTIALLY ONE MOLECULAR PROPORTION OF PHENOL AND SUBSTANTIALLY ONE MOLECULAR PROPORTION OF THE ESSENTIALLY ACID FREE CONDENSATION PRODUCT OF ACETONE AND A PRIMARY AROMATIC AMINE POSSESSING ONLY AMINO AND HYDROCARBON GROUPS AND CONSISTING SOLELY OF THE ELEMENTS CARBON, NITROGEN, AND HYDROGEN, THE MOLOECULAR PROPORTION OF THE ACETONE-AMINE CONDENSATIONB PRODUCT BEING BASED ON THE ASSUMPTION THAT IT IS TRIMETHYLE DIHYDROQUINOLINE. 